According to the currently used method for manufacturing a water-proof and dust-proof electronic product, there is normally a rubber strip enclosed between two plastic casings covering an electronic component and then the rubber strip is laminated with the two plastic casings by pressure to avoid external moisture and dust entering the interior of the two plastic casings. However, such method still cannot guarantee a 100% water-proof effect, and moisture may infiltrate via gap between the plastic casings and the rubber strip and cause damage to the electronic component. Another method for manufacturing an electronic product is to use an in-mold forming technology. An electronic component is firstly mounted on a film, and then the film with the electronic component is placed in an injection mold. Then, a melted plastic material is injected into the injection mold, such that the melted plastic material and the film with the electronic component are bonded together. Although such method may achieve a water-proof effect, the yield rate of the injection method is low, and the electronic component disposed on the film still may be collided by the injected plastics and become damaged.